The present invention relates to a single-push-button-controlled automatic umbrella and, more particularly, to an automatic umbrella wherein, the opening and collapsing is controllable by a single push button.
In the past, several types of automatic umbrellas have been disclosed, to cite for example, U.S. Pat. No. 3,856,030 to Sato. In that prior art, the umbrella employs two push buttons for opening and closing respectively. Such an umbrella is not only complicated in construction but is also difficult and troublesome in assembling, and hence is of high cost. To obviate these shortcomings the present inventor discloses in U.S. Pat. Nos. 4,534,374 and 4,548,222 a different and improved type of automatic umbrella. In operation, the umbrella may be opened by depressing the single push button in the first stage. When the umbrella which has been opened is next to be closed, the push button now in its second stage is first slid downwardly and then depressed. Although the single push button opening and closing mechanism thus constructed simplifies the operation and construction in an umbrella, nevertheless, it is still a way from perfection in view of its requirement that in operation the user's thumb has to perform two different actions. In addition, a larger space has to be provided in the grip for pulling up and down of the push button. Also, the resiliency of the spring pawl formed integrally with the locking head may be adversely affected after being used for some time as a result of restriction by its shape and material.